My Jimmy tilts slightly to the right in the rear and I've been wondering if it's the springs. Lots of good info here. I'll have to check my codes. Seems like I learned years ago that it has the heavier towing or maybe off road package, and it's always ridden like a wagon, so I'm really curious if it has the 1400 lb springs. I'll let you know what I find. 😁

 

Did he offer to come help with the installation?

 

Nope. To ask would have been cruel! LOL

 

Oh good. I'm glad that this info might help others. If you can, also list the torsion bar RPOs that go with your overall suspension RPO. As you noticed, I was trying to create a cross-reference for these.

If you are sagging on one side in the rear, then it is easy to imagine that you have a bad spring. Perhaps one of the leaves broke? You'll of course want to replace the springs as a pair to make sure the ride height and spring-rates are the same. After ~20 years, I'm sure the leaf springs in many of our Blazers are sagging.

 

So when exactly is snow season going to be over here in Idaho? Just asking so I have an idea when I can get back to work on the purple jimmy project lol.. But seriously can't wait for your write up on this project.

 

Snow season is coming to an end here. I still have a bit of snow on the back porch. Although I do not expect much more, there is still the possibility of getting enough so that I'd want the truck. The main limitation is that I need to bring the 82 Prelude into the garage to diagnose I likely vacuum leak at the carburetor base. Once it gets running and April has come around, then I might have time to dig into the leaf springs.

I'll be sure to take pictures and take notes. I'm thinking I'll buy myself an angle grinder to cut off the old mounting bolts since I have all new replacements anyway. That should make the removal much easier. Interestingly, although the new replacement bolts are the proper grade, I was surprised that the shackle bolts did not use the pinched nut retention method but rather Nylok style nuts. I'll likely still install them with Loctite anyway. The new u-bolts also did not come with any retention system built into the nuts. The u-bolts and the nuts are of a fine thread with the nuts being about 2x taller than normal nuts.

 

You can always squeeze the nuts in a vise if you prefer those but nylocks should by fine on their own. And I have never seen any kind of retention used on U-bolts. My understanding is that they are torque to yield (TTY) and shouldn't be reused.

 

Which RPOs are the torsion bars? I could just take a picture of my sticker and send it, or post here. 😁

 

If you could post your RPO sticker that would be great! You probably want to delete or redact the VIN on it first though for privacy reasons.

However, to answer your question, for 4wd Blazers, the RPOs for the different torsion bars I have found are 6WH/7WH, 6WJ/7WJ, 6WK/7WK. The overall suspension RPOs I've found are ZW7, ZQ1, Z85, ZM6. I'm pretty confident of most of my cross-referencing but I haven't been able to confirm that the ZW7 and ZQ1 are basically the same except for the self-leveling shocks on the rear that come with the ZW7.

I only have a few vehicles listed so far. A surprising result so far is that for the ZR2, the front t-bars have a very high rating but the rear springs have a low rating. This might because it is a 2door and not a 4door body.

I've attached what I've been able to create so far.

 

I got the springs for my 2001 ZR2 from General Spring as they are local to me. I picked them up to save shipping. Was a bit more difficult to install as I changed the bushings top and bottom. Happy with them and they fixed the Carolina squat the truck had